1. Field of Invention
The present invention relates to an electronic device, and more particularly to an electronic device structure with a main board capable of shifting towards triaxial directions.
2. Related Art
Recently, with the rapid development of the technology, computer apparatus has become indispensable in working or living. The electronic products are increasingly developed towards being miniaturized and being light, thin, short, and small. For users usually moving outside, portable electronic products such as notebook computers are more conveniently carried, and thus greatly improve the using convenience. A main board must be assembled in the notebook to serve as a core member of a computer system, so as to successfully execute preset functions of the peripheral hardware electrically connected to the main board.
For the recently common manner of fixing the main board, a plurality of conductive bosses serving as the fixing members is disposed on a lower case of the notebook computer device, and a plurality of through holes corresponding to the bosses is opened on the main board. The main board is placed on the bosses with an appropriate distance kept between the main board and lower case. Then, a plurality of screw bolts respectively passes through the through holes of the main board, and is locked on the bosses, such that the main board is suspended through the bosses, thereby preventing weld joint contacts on a back surface of the main board from directly contacting with the case to result in a short circuit. Finally, the upper case is combined with the lower case, and the main board and the two cases are serially locked together.
For the conventional manner of locking and fixing the main board through the bosses, although the main board may be tightly fixed between the two upper and lower cases, the main board directly contacts with the case, thus lacking a buffer mechanism design. When the notebook computer is impacted, or falls on the ground, the electronic members electrically disposed on the main board may be damaged due to the impact, or the main board may be displaced as the fixing position is broken.
In order to solve the above problems, ROC patent No. 576515 disclosed a main board fixing device, in which a flexible pin is used to replace the screw to fix the main board, thereby increasing the buffer capability of the main board during impact. Although ROC patent No. 576515 provides good buffer capability of the main board, after a long time of use, the pin may be loose by reason of the aging of the material, so the fixing effect is poorer than that of the screw.
Particularly, for a main board with a ball grid array (BGA) package, no matter for the manner of fixing the main board through the screw or through the pin, when the screw is tightly screwed or the pin is inserted in the pin hole, the main board cannot shift in a horizontal direction (i.e. the X axis direction and the Y axis direction) because of the fixing of the screw or the pin, so the stress of the main board can only deform towards a vertical direction (i.e. the Z axis direction). In this manner, the BGA package structure of the main board may be damaged, such that the electrical connection may be lost between the chip and the main board.